The present invention relates generally to the collection and filtration of body fluids. More specifically, the present invention relates to the leukodepletion of red blood cells.
In a variety of therapies, such as transfusion and transplants, body fluids, especially blood components, such as red blood cells, platelets, plasma, and bone marrow, are infused from one or more individuals into a patient. Three principal indications for the transfusion of a blood component exist: 1) deficiency in oxygen-carrying red blood cells; 2) deficiency in hematologic factors related to blood clotting, including platelets or protein coagulation factors; and 3) deficiency in plasma volume.
Patients requiring a transfusion do not receive whole blood, but, rather receive the specific component required to overcome the clinical deficiency. For example, patients undergoing chemotherapy or radiation therapy require primarily platelets and to a lesser degree red blood cells. Bone marrow or other organ transplant and dialysis patients generally require only red blood cells.
Some blood components, such as leukocytes, are generally unwanted because they are not relevant to the therapeutic effects of oxygen-carrying red blood cells, platelets, or plasma. Leukocytes also have been implicated as increasing the risks associated with blood transfusions for their role in alloimmunization to HLA antigens and post transfusion infection by acting as virus carrying cells. Thus, a filtering process is used to remove leukocytes in approximately 10% of the transfused blood components, although this percent may increase in the future. This process is called leukodepletion.
In collecting blood, commonly an anticoagulant is added to the whole blood collected from the donor. Whole blood can be separated into its components. The separated components can be placed in storage containers. For example, red blood cells are collected and stored in containers that include a storage solution such as Adsol.RTM. available from Baxter Healthcare of Deerfield, Ill.
As previously stated, it may be desirable to remove the leukocytes from, for example, red cells before they are transfused. A typical leukodepletion filtering process comprises passing the blood component that is housed in a container through a filter designed to capture leukocytes without damaging the blood components. To improve recovery of the blood component, a storage solution is used to rinse any remaining blood components through the filter.
The current process utilizes separate containers to store both the blood component and the subsequent rinse solution. Various concerns exist with the current approach. For instance, using multiple containers increases manufacturing costs and is burdensome for the personnel. In addition, a possibility of contamination exists when solutions are housed in multiple containers. Furthermore, a disadvantage of the present system is that typically, blood components will remain on the walls of the storage container reducing yield.
Therefore, a need exists for an improved method for the leukofiltration of blood components, as well as a container useful in performing such method.